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Assignment 3
 

Assignment 3

Certain mutations in the b-globin gene result in altered amino acid sequences in the hemoglobin molecule that produce a protein with an increased affinity for binding to oxygen. One example of such a mutation produces a molecule called hemoglobin Yakima. Yakima involves an amino acid substitution mutation at position 99, where aspartic acid is replaced by histidine. Individuals with these mutant forms of hemoglobin often show redder-than-average complexions. Working within the HemogloblinLab, select the Blood Samples view and scroll through the patient case histories searching for the patient whose complexion matches this description.

Once you think you have found this patient, select the Microscope view and evaluate the patient's red blood cells for any obvious defects. Select the Gel Electrophoresis view.
1 .       Does the migration pattern of this patient's hemoglobin indicate a mutation in the protein? If your answer is yes, does this patient appear to be homozygous or heterozygous for this mutation?  



2 .       Select the Peptide Sequence view and click the Find Difference button to identify the altered amino acid sequence for this patient.

What is the mutation that appears? Is this mutation indicative of hemoglobin Yakima? Provide reasons why you think this mutation may increase the affinity of oxygen for binding to hemoglobin Yakima.  








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